Strip feeding device with retractable pins



Nov. 17, 1959 B. J. BEVAN STRIP FEEDING DEVICE wim RETRACTABLE PINS Filed May 18, 1955 2 Sheets-Sheet 1 INVENTOR. Bezmqa L/B mw By 'm aw lzramms "Nov, 17, 1959 B. BEVAN STRIP FEEDING DEVICE WITH RETRACTABLE PINS Filed May 18, 1955 2 Sheets-Sheet 2 INVENTOR 4/3! w ATTORNEYS United States Patent STRIP FEEDING DEVICE WITH RETRACTABLE PINS Bernard J. Bevan, Highland Park, 111., assignor to Smith- Corona Marchant Inc., a corporation of New York Application May 18, 1955, Serial No. 509,316

14 Claims. (Cl. 197133) This invention relates to wheels having a plurality of peripherally spaced retractable pins and more particularly but not exclusively to such wheels known as pin wheel strip feeding devices in which the individual feeding pins are simultaneously extensible and retractable relative to the periphery of the device.

The primary purpose of this invention and its use as disclosed, is to provide a device for attachment to the record platen of a writing machine which will enable the record feed to be quickly and easily changed from positive pin feed to friction feed, and vice versa.

Heretofore positive pin type strip feeding devices have been in common use and are well known. Two such previously known types are pin wheels having fixed peripheral pins and wheels having cyclicly projecting and retracting pins. Over prior years both of these prior art pin wheels have been extensively modified and developed for use in machines using strip records of the roll or fan fold type with feed holes provided in the edges of the records. However it has become desirable to eifect rapid changes from pin hole strip feeding to platen friction feeding of the record and to effect such a change with the strip feeding devices, as mentioned above, necessitated a change of platens in many instances, consuming as much as eight hours change-over time depending upon the installation and adjustments to the machine made necessary by such a change. There has been trend in development of the cyclicly projected type pin wheel to incorporate mechanism for shifting the cyclic period, when the pins are projected, to a sector of platen rotation during which the record is not engaged, but such devices are complex and costly.

Recently several different styles of simultaneously extensible and retractable pin wheel feeding units have been developed, using actuating linkage materially distinct from that of the present invention. One such unit uses a plurality of spring links, one for each pin, for pin extension and retraction, thus increasing the number of parts and assembly time for the unit. Another unit uses pivoted pins that can easily shift to retracted position by reason of tangential loads on the feed pins, thus must utilize a substantially positive locking nut or locking pin structure to maintain the various elements of the unit in extended or retracted position.

This invention provides a simultaneously extensible and retractable pin wheel feed unit wherein the pins are moved radially outward or inward in a hub or body by a small incremental rotation of a slotted disc. The pins are maintained in radial disposition by a double set of spaced radially extended grooves in the unit body and a juxtaposed slotted cam plate fixed to the body, whereby pure tangential force on the feed pins will be wholly absorbed by the fixed hub and plate. To counteract radially inwardly directed forces on the feed pins, a friction disc is disposed in self biased engagement with the cam plate. The pin wheel hub is adaptable for easy attachment to existing writing machine platens. When installed on a machine platen, change-over in either sense between pin feed and platen friction feed with the present invention can be eifected in a few seconds either by hand or by using a small tool such as a screw driver, thus eliminating the need of special tools to loosen nuts or unlocklocking pins.

Accordingly a major object of my invention is to provide a novel mechanical pin wheel having means for simultaneously extending and retracting radially directed teeth from a cylindrical body.

A further object resides in the provision of acompact, rugged pin wheel strip feeding device having a plurality of feeding pins that can be simultaneously withdrawn into the device to leave a smooth peripheral surface.

A still further object resides in a provision of a pin wheel strip feeding device having radially shiftable pins each guided within a set of opposed guide tracks and each positively engaged by a control element for simultaneous projection and retraction. v

Still another object residues in providing a retractable pin wheel strip feeding device wherein all pins are positively and simultaneously moved into or out of operative position by an incremental rotation of a control element without the necessity of further mechanical actuation such as loosening of nuts or unlocking locking pins.

A further object resides in the provision of such a novel pin wheel feed device in coaxial abutting interlocked relationship with a cylindrical platenof a writing machine.

A still further object resides in the method of constructing a pin-carrying unit of two part hollow construction with accurately aligned radially directed pin holes and sets of opposed groove tracks in the twoseparable parts.

Further novel features and objects of this invention will become apparent from the following detailed description and the appended claims taken in conjunction with the accompanying drawings. The drawings illustrate a preferred embodiment of the invention, in which:

Figure 1 is a perspective view of an assembled writing machine platen employing the present invention;

Figure 2 is an end elevation view of a pin wheel unit, with pins projected to operative position, and with sec-, tions partially broken away to show the structural coop-- erationbetween the various elements;

Figure 3 is similar to Figure 2 but illustrates the pins in a retracted position; 7

Figure 4 is an exploded perspective view of the strip feeding device and the cooperating end of a platen;

Figure 5 is a section taken on line 55 of Figure 2;

Figure 6 is an elevation view of a modified embodiment of the pin wheel body with control plate, friction plate and clip removed; and

Figure 7 is a section taken on line 77 of Figure 6.

These pin-wheel strip feeding devices as used on writing machine platens function in the manner of sprocket wheels and the radially projecting retractable pins function as sprocket wheel teeth to move a record medium upon rotation of the machine platen.

' Withreference to the drawing, Figure 1 illustrates a platen roll 20 with a pin wheel unit 22 mounted in each end. A tubular member 24 pases through the center of disposed strip feeding pins 30 progressively engageable during machine operation within longitudinally disposed marginal feeding configuration 32 of arecord strip 34 Each pin' The platen roll consists of an outer tubular sleeve 36, preferably of rubber or like composition, disposed over a second tubular sleeve 38 made of metal. To assure unitary rotation of the pin wheel units 22 and platen roll 20the annular ends of the tubular metal sleeve 38 are provided with slots 40 which are engaged by radially disposed pins 42 fixed in the pin wheel units 22. Pins 42 are of suflicient length to firmly interlock with the slots 40 in the metal sleeve 38, but do not project into engagement with the outer friction sleeve 36. As shown, the ends of bothinner and outer sleeves 36 and 38 abut side, shoulders 43 of the pin wheel units 22 which have peripheral cylindrical rims 44 coextensive with the outer cylindrical surface of platen roll 20.

Each pin Wheel unit 22 consists of a hollow body 46 coacting with a face plate 48 secured to rotate with body 46 by a pin 50. Body 46 is provided with a central hollow sleeve 52, radial wall 53, enlarged boss 54 and cylindrical axially directed rim 44. The edge or rim 44 is recessed to form an annular shoulder 56 on its inner periphery.

The face plate 48 is provided with an aperture 58 with a diametral dimension enabling it to be closely disposed over the hollow sleeve 52 with plate 48 resting within the rim 44 on shoulder 56. Body 46 and plate 48 thus provide a hollow unit with two spaced parallel circular end walls joined by the circumferential rim 44. A plurality of apertures 59 are circumferentially spaced ground the periphery of rim 44 and are radially directed relative to the axis ofbody 46 as is clearly apparent in the perspective view, Figure 4. The apertures 59 are coextensive with guide track grooves 68 and 62 radially provided respectively on the inner face plate 48 and the radial wall 53.

Strip feeding pins 30 are individually disposed within the hollow body 46 in sets of opposed guide grooves 60 and 62 for radial sliding movement along the guide tracks so their strip engaging ends can be projected radially from the outer cylindrical surface of rim 44 through apertures 59 or be retracted into the hollow body 46. Also provided in face plate 48 are a plurality of radially directed slots 66, each slot being situated to overlie and intersect one of the grooves 60. Transversely extending from adjacent the inner end of each pin 30 is a fixed stud 68' which extends through the radial slots 66 in face plate 48. The extent to which pins 30 are radially movable is limited by engagement of stud 68 with the ends of the slots 66.

Radial retraction and projection of the pins 30 relative to body 46 is accomplished by means of a control plate 70 coaxially journalled, in abutting relation to the outer surface of face plate 48, on the extended hollow sleeve 52. The outer periphery of contact plate 70 is formed as an annular axial flange directed away from body 46 with its outer cylindrical surface substantially coextensive with rim 44 of the body 46. The flat radial portion of control plate 78 disposed in abutting relation with face plate 48 is provided with a plurality of slanted camslots, preferably arcuate, which gradually diverge from a location adjacent the center aperture of the control platen. Then number of cam slots 74 is equal to the number of strip feeding pins 30, and pin studs 68 project through the radial slots 66 in face plate 48 into the corresponding cam slots 74 in control plate 70. An angular movement of control plate 70 relative to the unitary body 46 and plate 48 causes shifting of the studs 68 and pins 30 as the studs are forced to follow the intersection of radial slots 66 and cam slots 74. The pins 30 "are thus shifted inwardly or outwardly depending on the direction of rotation of control plate 70. The angular movement of control plate 70 is limited to the arcuate angle included between radii passing through the inner and outer ends of the cam. slot 74.

The control plate 70, placed in position on sleeve 52 with the cam slots 74 cooperating with studs 68, is held in fixed relation to the assembled body 46 and plate 48 by a friction plate 76. The friction plate 76 has a central aperture 77, disposed over sleeve 52, and an oif-set peripheral edge 78 that bears against the outer face of control plate 78. The separable components of the pin wheel unit 22 are held in fixed axial relationship by a retaining clip 88 cooperating with an annular groove 82 in the extended hollow sleeve 52. In order to assemble clip in annular groove 82, friction plate 76 is slightly sprung, causing its peripheral edge 78 to exert frictional force against the control plate 70 and also forces control plate 78 to bear tightly against the face plate 48. Frictional drag thus created by the spring friction plate 76 is sufiicient to maintain the control plate in a set position and will thereby maintain pins 30 in a projected or retracted position during operation of the writing machine. A plurality of slots 84 are provided in the control plate peripheral flange to enable control plate 70 to be turned by hand or by suitable means such as a screwdriver, to render the strip feeding pins operative or inoperative.

Method of construction of pin-wheel body Figure 5 illustrates the hollow construction of the preferred body unit made of two parts 46 and 48 and Figure 7 illustrates an alternate construction wherein the body 46' is integral and provided with suitable radial bores 98 and one side wall having apertures 92 intersecting the bores. In certain writing machine installations, particularly as required by the 13.8. Signal Corps, weight is a primary factor to consider, hence the hollow lighter weight pin-wheel body disclosed in Figures 1-5 is the preferred construction of this invention.

'The construction of the solid pin-wheel body 46 is relatively simple. The body unit 46' with all external surfaces preformed is placed in an indexing drill jig and the radial holes drilled or bored to the proper depth. The unit is then removed from the drill jig and placed in a second jig locating on the center hole and one of the radial holes 90 and slots 92 are pierced through the side wall of the body to intersect corresponding holes 90. The pins 38 can be inserted from the periphery and studs 68 inserted through the slots 92 and press-fit in the pins 30.

The method of producing the two part pin-wheel body 46 and 48 is more intricate as the radial holes 59 must be accurately aligned with the radial grooves 60 and 62 in the separable plate 48 and cup-shaped body 46 respectively. The matched plate 48 and body 46 are pressed together and held in alignment by the pin 50. Both ele ments are clamped together in an indexing drill jig and the radial holes 59 drilled or bored through the outer rim 44 of body 46. Without removing the assembly from the drill jig, the clamped plate and body is reamed with an end cutting reamer down to the sleeve hub 52 which is integral with body 46. In this manner the radial grooves 60 and 62 are formed accurately coextensive with the radial holes 59 in rim 44. Plate 48 is then disassembled from body 46 and slots 66. pierced to intersect grooves 60. During the piercing operation plate 48 is located on the center hole 58 and the hole in which pin 50 locates. In this embodiment the pins 30, with studs 68 pre-lxed, are placed in the body '46 prior to fitting the plate 48 in the rim recess 56 and in engagement with the pin 50.

For both body styles, the control plate 70 is placed over sleeve 52' or 52. with its cam slots 74 engaging the pin studs 68, the friction plate 76 placed over sleeve 52 with its edge 78 abutting control plate 70 and the retaining clip 80 fitted into the sleeve groove 82.

The present structure presents a relatively simple but efiicient and dependable means of individually mounting a series of feeding pins forsimultaneous movement either in orout of the periphery of a pin supporting body. When used in a writing machine in conjunction with a platen roll the machine is quickly adaptable to be used with preperforated record strips which will be fed by means of extended pins of the pin wheel strip feeding units or a perforated or unperforated record strip may be advanced by other feeding means such as friction feed by the rubber or composition platen roller with the pins of both units retracted. The device of this invention utilizes relatively few simple parts easily adapted to existing writing machine platens. The feed pins are rigidly supported in sets of opposed grooves and their movement by the control member is direct and positive with the number of moving parts kept to a minimum. The feed pins are constrained for sole movement in a radial direction thus eliminating any wear due to rotation or pivotal movement. By eliminating a plurality of minute interconnecting linkages a substantial savings in cost of producing parts and assembly of the complete unit is realized.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. A retractable tooth sprocket wheel comprising a series of individual teeth adapted to be projected and retracted; a body means carrying all of said teeth having individual radially disposed guide means for each of said teeth; and a control element rotatably disposed on said body means for limited angular displacement and having slotted cam means operatively engaged with a projection on each tooth to enable simultaneous projection of all of said teeth from said body means upon movement to one of its limited positions and to retract said teeth into said body means upon movement to the other of its limit positions.

2. A retractable tooth sprocket wheel comprising: a series of individual teeth adapted to be projected and retracted; cylindrical body means adapted to be mounted on a rotatable means, carrying all of said teeth internally and including a plurality of radially directed guide means for said teeth; a control member coaxially mounted on said body member for limited angular displacement relative thereto including means integral therewith and having slotted cam means coacting with each tooth to project all teeth exteriorly of said body means or retract all'teeth into said body means depending on movement to one of its limit positions; and frictional means coacting between said body means and said control member tending to prevent relative movement therebetween.

3. A pinwheel having a plurality of simultaneously retractable pin elements comprising: a body including a cylindrical outer surface with integral means including aperatures through said cylindrical surface for guiding and enabling projection and retraction of said plurality of individual pin elements through said cylindrical surface; means non-rotatably fixed to said body, retaining and restraining each of said pins for movement solely in a respective straight limited path relative to said means for guiding and enabling projection and retraction of said pin elements; and a single element rotatably mounted on said body and cooperating with all of said pin elements to simultaneously move said pin elements in said respective straight paths.

4. A pinwheel having simultaneously retractable pins comprising a two part hollow body with a circumferential wall and two substantially parallel end walls, a plurality of sets of opposed substantially radial grooves in the inner faces of said end walls, each set of grooves having their outer ends coextensive with an aperture provided through said circumferential wall, a plurality of pin means disposed in said grooves, and means for simultaneously 6 projecting and retracting all of said pin means through said apertures.

5. A pinwheel having simultaneously retractable pins comprising: a substantially cylindrical body, a plurality of substantially round pins each having a stud fixed thereto, means in said body structurally cooperating with said pins and studs confining said pins to movement solely in limited substantially radial paths from within said body to a substantially radially projected position, and means rotatably mounted on said body and engaging said studs for simultaneously extending and retracting said pins.

6. A pinwheel having simultaneously retractable pins comprising: a substantially cylindrical body; a plurality of pins, each having a stud fixed thereto; means on said body cooperating with each of said pins restraining movement of said pins along individual substantially radial paths; and two relatively rotatable plates mounted on said body each plate including a slot for each stud, the slots in one plate being cam slots and the slots in the other plate being guide slots said plates and slots disposed with said studs projecting through paired slots in said two plates and said slots being so disposed relative to each other that rotation of one plate relative to the other will move said studs and pins along said substantially radial paths.

7. A pinwheel as defined in claim 6 wherein said plates and slots are arranged relative to each other and to said body so relative rotation of said plates will simultaneously cause the intersections of all said paired slots to move radially inward or outward.

8. A pinwheel as defined in claim 7 wherein one of said plates has radially disposed slots and is fixed to said body, and the other of said plates has cam slots all similarly shaped and slanted from a radial position.

9. A pinwheel as defined in claim 8 wherein said pins are round and radial grooves are provided in said body and said one plate to guide said pins in a radial path.

10. A pinwheel having simultaneously retractable pins comprising: a cup shaped body having an end wall with an integral substantially axially directed annular rim provided with a plurality of circumferentially spaced apertures, an equal plurality of substantially radially directed grooves in the inner face of said end wall each coextensive with a part of one aperture, and an annular recess in the edge of said annular wall forming an annular shoulder on its inner periphery, a pin with a stud fixed substantially transverse to its axis disposed in each of said grooves, said pin being adapted to slide along said groove for projection through said apertures or retraction wholly within said body; a plate disposed in said body recess on said shoulder having a plurality of substantially radial slots equal in number to said apertures, said plate being non-rotatably attached to said body with said slots aligned with said grooves and with said studs projected through said slots and beyond said plate thereby de fining a limited substantially radial path for movement of said pins; a control member coaxially rotatably mounted on said body adjacent said plate having a plurality of slanted arcuate slots equal in number to said studs and arranged with the ends of said studs disposed in said arcuate grooves; anda friction plate stressed between said body and said control member to force said control member tightly against said body.

11. A mechanical device comprising: a unit assembly consisting of two spaced apart parallel coaxial circular walls, an annular circumferential rim wall joining the outer peripheries of said two circular walls, circumferentially spaced apertures through said rim wall, radial guide tracks in the inner faces of said circular walls co extensive with said apertures, and radial slots in one of said plates intersecting the guide tracks in said one plate; a plurality of pins slidably disposed in said guide tracks, each pin having a transverse stud projecting through the slot intersecting its respective groove so said pins will be constrained solely for sliding movement for projection through said apertures or retract-ion within said unit assembly; and a control plate having a plurality of slanted cam slots, one for each stud, coaxially rotatably mounted relative to said unit assembly with the end of each of said studs disposed Within a cam slot so rotation of said control plate relative to said unit assembly will simultaneously move said pins radially outward or inward.

12. A mechanical device as defined in claim 11 wherein a clip and retaining disc maintain said control plate in tight friction fit against said unit assembly.

13. In a writing machine having a cylindrical rotatable platen, an auxiliary unit comprising: a body having a cylindrical rim substantially the same diameter as said platen with internal radially disposed guide means for a plurality of teeth and apertures in said rim coextensive with said guide means; teeth disposed in said guide means for projection through said apertures and retraction wholly Within said body; a control element coaxially and rotatably disposed on said body means for limited angular displacement and directly engaged with each tooth to enable simultaneous projection of all teeth from said body means upon movement to one of its limit position and to simultaneously retract all of said teeth into said body means upon movement to the other of its limit positions; and

a 8 means maintaining said body and platen in coaxial abutting interlocked relation.

14. In a writing machine having a cylindrical rotatable platen, an auxiliary inwheel unit with simultaneously retractable pins comprising: a substantially cylindrical body, a plurality of substantially round pins each having a stud fixed thereto, means in said body structurally cooperating With said pins and studs confining said pins to movement solely in limited substantially radial paths from within said body toa substantially radially projected position, and means rotatably mounted on said body and engaging said studs for simultaneously extending and retracting said pins; and means maintaining said body and platen in coaxial abutting interlocked relation.

References Cited in the file of this patent UNITED STATES PATENTS 1,945,515 Norton Mar. 6, 1934 1,977,194 Malkowsky Oct. 16, 1934 2,042,017 Papst May 26', 1936 2,102,651 Sherman Dec. 21, 1937 2,271,306 Nichols Jan. 27, 1942 2,724,279 Davidson Nov. 22, 1955 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 2,913,093 November 17, 1959" Bernard J Bevan It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should readas corrected below.

Column 2, line 20, for "residues" read resides line 61, for "pases" read passes column 3', line 38, before "can" insert the numeral "64"; line 53, for "contact" read control line 61, for "Then" read ihe column 4, line 18, after "flange" insert the numra'l "79's Signed and sealed this 7th day of June 1960 (SEAL) Attest:

KARL .AXLINE ROBERT C. WATSON Attesting Officer Commissioner of Patents 

